800cc on the cheap. 10mm+ stroker with lamey cylinders

[yamanube]

Last years blown 760 left me wanting more power and even more reliability so I did a little research and jumped in head first on a 66E swap. So far things have gone good and I am still under budget but there is still quite a bit to go.
Im not building a monster just decent power with (what should be) nearly stock reliability and keep total costs under $1k. So here is the breakdown so far.

Parted out 701, TL ignition, Bpipe, and other parts/spares for the 701/760 ~$2100

66E motor (complete and never installed in a ski) -$1300
Dual intake setup courtesy of Brandon Reed and some smart shopping -$140
Dual 48mm Riva Powerbombs -$600
GP800 motor mounts -$60
Waveeater PV clips -$60
WDK wet pipe -$650
Kart Tank -$50
WDK Engine mounting kit -$315
JSS throttle coupler -$40

So I am roughly $940+/- into my build, can I stay under $1k? Maybe, but Ill have to shop carefully and wait on some parts. Will it be more reliable than a similarly powered 62t based motor, should and will hopefully give me more power than $1k spent on a stock 701 would.
This year the motor will stay internally stock (bore, compression, porting), stock electric powervalves, and stock electronics. Only modifications will be a pipe and carbs, this will hopefully give a nice baseline and help give accurate information for others looking to do the swap. If I am happy with the power I will likely keep this setup for a while as its clean, simple, relatively cheap and reliable. I will be using a stock pump with all combinations of a stock cone, WW cone, 14/18 concord and 15/19 skat. Anyways here are a few pics of the intake setup..contact Breed6903 if you want one and he can help you out (price may vary). He also makes some bitchin' bottom cases that allow the use of stock 701 "bedplates" and electronics.

 

[WaveDemon]

nice progress. you did the same thing I was doing for the intake set up before I had my exhaust problems.

 

[yamanube]

nice progress. you did the same thing I was doing for the intake set up before I had my exhaust problems.

It should work out well, it was cheap and required no modification to the motor or intakes and keeps the carbs nice and tight against the motor. Brandon should have complete intake setups available for puchase soon. I will likely be running his new improved B pipe style wetpipe and hopefully be able to run stock tank and waterbox.

 

[dbrutherford]

Are thosw Kawasaki 650 Intakes?

 

[yamanube]

Are those Kawasaki 650 Intakes?

They are GP800 intakes now :lmao:

 

[WaveDemon]

It should work out well, it was cheap and required no modification to the motor or intakes and keeps the carbs nice and tight against the motor. Brandon should have complete intake setups available for puchase soon. I will likely be running his new improved B pipe style wetpipe and hopefully be able to run stock tank and waterbox.

any news on when his exhaust will be available?



here is a cheap mod for you...

cut the bottom of the cylinders to lower port timing + raise compression.

 

[WaveDemon]

They are GP800 intakes now :lmao:

I used 760 intake + reeds.

may switch that up though...

 

[yamanube]

any news on when his exhaust will be available?



here is a cheap mod for you...

cut the bottom of the cylinders to lower port timing + raise compression.

Still waiting, looking like still a month or two out (or more?). For this season, the motor will stay stock. It has maybe 1 hour on it, Im not even going to pull the head off this season, brand new Yamaha assembled motors are nice :biggrin:

I used 760 intake + reeds.

may switch that up though...

That is what Brandon was doing, I did some research and looked at some pics and shopped around. These manifold fit EASY and require no cutting, less holes and look clean.

 

[WaveDemon]

Still waiting, looking like still a month or two out (or more?). For this season, the motor will stay stock. It has maybe 1 hour on it, Im not even going to pull the head off this season, brand new Yamaha assembled motors are nice :biggrin:



That is what Brandon was doing, I did some research and looked at some pics and shopped around. These manifold fit EASY and require no cutting, less holes and look clean.

right on.

the kawi is a cleaner install.

 

[waxhead]

please please please
dont ruin that lovely gp800 intake tract buy putting that plate across it

Good luck on the conversion
i have ridden a gp800 engine in a stand up and its very nice

 

[yamanube]

Looks like I may be going with a WDK wet pipe setup due to time and money constraints. Maybe upgrade next year if something better is available but for now I would rather ride 100% of the season at 90% of my potential power than 90% of the season at 100% potential power.

 

[yamanube]

Bought a WDK wet pipe and updated my numbers. I am about $775 into it so far, right now I know I need an upright mounting kit, a carb coupler and a gas tank. I probably end up a tick over $1k but if I can find a deal on an upright mounting kit or mount my engine slanted I should at or under my budget. Can't wait to fire this pig up!

 

[WaveDemon]

fyi, if you install your motor slanted you'll have to relocate your battery.

 

[yamanube]

fyi, if you install your motor slanted you'll have to relocate your battery.

Yeah, that is my absolute last resort to get on the water. I don't think it will come to that though.

 

[yamanube]

Installed the waveeater powervalve clips today...nice little piece of insurance and nifty little parts. This should work well until I go to gas valves.

 

[E rok Wilbs]

Installed the waveeater powervalve clips today...nice little piece of insurance and nifty little parts. This should work well until I go to gas valves.

Do you mind elaborating a little bit more on what you did with the powervalves? This is a great build and you and demon seem to know alot about these things, any extra info is greatly appreciate. Also where/who did you buy that exhaust system from? The exhaust is my main dilemma that I would love to figure out before I dive head first into this beast. Thanks again.

 

[WaveDemon]

Do you mind elaborating a little bit more on what you did with the powervalves? This is a great build and you and demon seem to know alot about these things, any extra info is greatly appreciate. Also where/who did you buy that exhaust system from? The exhaust is my main dilemma that I would love to figure out before I dive head first into this beast. Thanks again.

as much as I hate to admit it, the wave eater clips are a must. they're a $.05 clip that keeps the pin in the PV from falling out. I've had 3 pins fall out on me in the few months I ran that motor.


the problem with the clips is they cost $60

having the pin fall out doesn't damage the motor, the PV's are designed not to fall into the cylinder and the pin can't go anywhere but next to the top of the PV. It just make the PV stop working correctly.

 

[yamanube]

Do you mind elaborating a little bit more on what you did with the powervalves? This is a great build and you and demon seem to know alot about these things, any extra info is greatly appreciate. Also where/who did you buy that exhaust system from? The exhaust is my main dilemma that I would love to figure out before I dive head first into this beast. Thanks again.

I bought a Waterdawg wet pipe used off of Suva. If I had another ski to ride or another motor to run for a while I would hold out for Brandon Reed to finish his B style pipe..it will look nearly identical to a Factory B pipe but will have a custom manifold and headpipe to accomodate the 800 motor, very cool. PM me with any questions and I can share the little information I have dug up on them.

as much as I hate to admit it, the wave eater clips are a must. they're a $.05 clip that keeps the pin in the PV from falling out. I've had 3 pins fall out on me in the few months I ran that motor.


the problem with the clips is they cost $60

having the pin fall out doesn't damage the motor, the PV's are designed not to fall into the cylinder and the pin can't go anywhere but next to the top of the PV. It just make the PV stop working correctly.

Ahh, I was under the impression that they could fall into the cylinder, either way, nice to have. I was blown away when I got them in the mail, $60 for two little pieces of spring steel.

 

[yamanube]

Got the WDK pipe and billet intake from Suva. The intake is going to a buddy since I already have the adapted 650 setup. Looking at them on the manifold side the billet WDK manifolds are BARELY larger than the 650 ones I have...with a little grinding work I think they will be nearly identical but the WDK ones look amazing, would be nice to have just for the bling. Now just trying to get an upright mounting kit and some small pieces (cooling fittings, carb coupler, flow control valve, etc) and have to test a couple gas tanks. Anybody have a used upright kit for sale?

 

[yamanube]

I ordered an 8.5L kart tank from Comet for $50 and will be buying an upright mounting kit this week. So far the totaly is roughly $940. I still have to buy a throttle coupler, some fuel lines/filters and a couple lord mounts for the chamber and from what I can tell that is all, looks like I will come in at or just under the $1,000 mark. Once the mounting kit comes in I can finally start putting things together and will probably hit the water in late April early May. The notorious water injestion issues with the WDK wet pipe have me a little nervous but there is nothing I can do about that now but keep it in mind and limit the amount of water sitting in the chamber as much as possible. I am excited to ride this ski and hope the setup is a little more enjoyable than I have been told it is.
I hope to get some pics of the assembly but my camera decided to take a crap so I may only get pictures of it when its done.